Bitcoin is like if someone made a real version of "Universal Paperclips"[1]. We now have a segment of the economy optimizing for creating cryptocurrency tokens with little-to-no use value but huge trade value. We already see the impacts on electricity capacity and some luxury goods (video cards). As these operations become more and more sophisticated, it's not inconceivable that they will eventually put price pressure on raw materials as well.
Maybe so, but at least mining is actually necessary to get gold out of the ground. Whereas running a distributed database and gambling can both be had for much less.
All of bitcoin could be run on a home PC from 2005. It can do about three transactions a second. And it is burning 0.5% of the electricity of the entire planet to do so.
This is basically a crime against humanity at this point.
Yes, but gold hasn't been explicitly designed to require ever increasing amounts of energy to extract ever diminishing quantities, and gold does have some practical use (approx 8% of annual production is used in mobile phones, televisions etc.)
Absolutely crazy.
[1] https://www.decisionproblem.com/paperclips/index2.html